I read before that the definition of "high blood pressure" has changed over time, and I finally wanted to find out if this is true, and if, by how much.  After searching for quite a bit, I found this great chart from Medscape that show the development of the JNC definition over time.  It’s clearly visible how the definition of "normal" dropped over time.

I don’t want to go into the reasons: The main question is whether we were initially wrong, or whether interest groups pushed it down. Make up your own mind.

Embedding the image does not seem to work, so check out the figure and the article.